Concrete structures and other building systems often incorporate joints that accommodate movements due to thermal and/or seismic conditions. These joint systems may be positioned to extend through both interior and exterior surfaces (e.g., walls, floors, and roofs) of a building or other structure.
In the case of a joint in an exterior wall, roof, or floor exposed to external environmental conditions, the expansion joint system should also, to some degree, resist the effects of the external environment conditions. As such, most external expansion joints systems are designed to resist the effects of such conditions (particularly water). In vertical joints, such conditions will likely be in the form of rain, snow, or ice that is driven by wind. In horizontal joints, the conditions will likely be in the form of rain, standing water, snow, ice, and in some circumstances all of these at the same time. Additionally, some horizontal systems may be subjected to pedestrian and/or vehicular traffic.
Many expansion joint products do not fully consider the irregular nature of building expansion joints. It is common for an expansion joint to have several transition areas along the length thereof. These may be walls, parapets, columns, or other obstructions. As such, the expansion joint product, in some fashion or other, follows the joint as it traverses these obstructions. In many products, this is a point of weakness, as the homogeneous nature of the product is interrupted. Methods of handling these transitions include stitching, gluing, and welding. In many situations, it is difficult or impossible to prefabricate these expansion joint transitions, as the exact details of the expansion joint and any transitions and/or dimensions may not be known at the time of manufacturing.
In cases of this type, job site modifications are frequently made to facilitate the function of the product with regard to the actual conditions encountered. Normally, one of two situations occurs. In the first, the product is modified to suit the actual expansion joint conditions. In the second, the manufacturer is made aware of issues pertaining to jobsite modifications, and requests to modify the product are presented to the manufacturer in an effort to better accommodate the expansion joint conditions. In the first situation, there is a chance that a person installing the product does not possess the adequate tools or knowledge of the product to modify it in a way such that the product still performs as designed or such that a transition that is commensurate with the performance expected thereof can be effectively carried out. This can lead to a premature failure at the point of modification, which may result in subsequent damage to the property. In the second case, product is oftentimes returned to the manufacturer for rework, or it is simply scrapped and re-manufactured. Both return to the manufacturer and scrapping and re-manufacture are costly, and both result in delays with regard to the building construction, which can in itself be extremely costly.